Crime | Lonnie Franklin 'Grim Sleeper' Found Dead Serial killer Lonnie Franklin Jr. died in prison cell By Evann Gastaldo Posted Mar 30, 2020 5:43 AM CDT Updated Mar 30, 2020 6:33 AM CDT Copied In this Aug. 10, 2016, file photo, Lonnie Franklin Jr., a convicted serial killer known as the "Grim Sleeper," is sentenced in Los Angeles Superior Court. (Al Seib/Los Angeles Times via AP, Pool, File) The "Grim Sleeper" is dead. Lonnie Franklin Jr., the serial killer who murdered nine women and a 15-year-old girl in Los Angeles between 1985 and 2007, was found unresponsive in his prison cell Saturday night, NBC News reports. The 67-year-old was on San Quentin State Prison's death row. There were no signs of trauma and the cause of death was not immediately clear; an autopsy will be performed, CNN reports. "I won’t say I’m pleased he died but at the end there was justice for all the bad things he did in his life," the mother of one of the victims tells People. "We can now be at peace." Franklin, a former city garbage collector, mechanic, and garage attendant at an LAPD station, got his nickname due to the "apparent hiatus" he took from killing, KTLA reports. Seven of his victims were killed between 1985 and 1988; the other three were killed between 2002 and 2007. But he was linked to four other slayings, and police believe he may have killed as many as 25 victims. Most were shot at close range, though two were strangled, before their bodies were dumped. A cold case task force used a DNA match to find Franklin in 2010. He was also convicted of the attempted murder of an eleventh woman. Read These Next New Fox star, 23, misses first day after car troubles. Iran's supreme leader makes first public comments since ceasefire. Her blood isn't compatible with anyone else's. Trump's spy chiefs back up his Iran claims, citing new intel. Report an error